Solution:
The reason some say Humpty had a great fall......he got a "push."
"Endlessly gutted and gorged" ...synonym for those two words is "full"- take off the end = "ful"
Answer = "Pushful."
second horse..." Namesake's grip" ...is a "scissors grip" ....to cut off the balls of 'the stewards' ( just for effect in the riddle)
Answer = "Scissors."
NB. Scissors, owned by Anne Biddle and ridden by Liam Ward, won the 1963 Timeform Trophy, but was disqualified in favour of Pushful, owned by steward, Lionel Brook Holiday.
A very controversial and bad decision, in my view.
Apologies if it was too awkward.